RE: Science Porn
May 13, 2016 at 7:07 am
(This post was last modified: May 13, 2016 at 7:09 am by Anomalocaris.)
(May 13, 2016 at 1:54 am)Alex K Wrote: And we only see those with Kepler that are precisely aligned to dim their stars. We just saw with Mercury how rare that is...Although most of these planets orbit stars less massive, and cooler than the sun. That means these stars are disproportionally dim compared to their diameters. Therefore the habitable zone around these stars are also disproportionally closer to the star relative to the diameter of star. Since a high percentage of these planets appear to orbit inside the inner bounds of the habitable zone, it is clear most of these planets orbit far closer to their Stars in relation to the size of their Stars than any planet in the solar system.
So we can expect of these planets, a high proportion can be expected to be seen transiting their stars more frequently than Mercury.
One point of fine print, sort of a fly in the ointment, for the illustrated habitable zone is this:
While a star's brightness decreases much faster than its mass, it's gravitational pull does not. This means the smaller the star, the more extreme any planets in its habitable zone will feel the tidal forces of its sun's gravity. So a high percentage of those planets in the lower part of that diagram are likely to be tidal locked to their stars. This can not be good for their habitability even if the amount of energy they receive from their sun would otherwise place them in the habitable zone.